Lecture 4 Flashcards
peptide bond has a partial blank
double bond
peptide double bond restricts blank
rotation
blank amino acids are involved in catalysis
very few
rotation angle around Ca-N bond
phi
rotation angle around Ca-C bond
Psi
secondary structures
alpha helix, beta sheet, beta turn, loop (unstructured)
alpha helix is a blank handed corkscrew
right
alpha helix has hydrogen bonding between blank protons and blank oxygens
amide, carbonyl
keratin secondary structure is usually a blank
alpha helix
two aa that interrupt alpha helices
proline, glycine
glycine is too blank which will not allow it to be in alpha helix
flexible
why proline interrupts alpha helices
creates a kink because it’s bent
beta sheet has a blank angle
extended
alpha helix has a blank angle
compact
secondary structure formed between linear regions of polypeptide chains. they are almost fully extended structures
beta sheet
beta sheets can be blank or blank in directions
parallel, antiparallel
sheets comprising blank chains are more blank than sheets of parallel sheets
antiparallel, stable
antiparallel beta sheets usually have a blank
beta turn
proline and glycine are good at making beta turns because glycine is blank and proline is blank
small, bent
secondary structure elements in blank proteins fold relative to each other to make tertiary structure
globular
tertiary structure of globular proteins is blank and is essential for correct biologic function
specific
blank folding is stabilized by interaction between side chains
long range
different stabilizing forces for tertiary structure
hydrogen, electrostatic interactions, van der waals interactions, hydrophobic effect, disulfide bonds
quaternary structure is stabilized by blank forces
similar to tertiary
hemoglobin has blank structure
multiple subunit
recognizable combinations of secondary structure that appear in a number of different proteins
motifs
motifs suggest blank function
common
discrete, independently fodled, compact unit present in protein
domain
a single domain may have blank
multiple functions
this destroys secondary and tertiary structure of proteins by interfering with electrostatic interactions
denaturation
denaturation does not affect this structure
primary
the property of certain substances to disrupt the structure of water and thereby promote the solubility of nonpolar substances in water
chaotropic
folding is local and driven by the tendency to decrease blank
free energy
gibbs free energy is defined as
T = absolute temp H = enthalpy S = entropy
free energy change for a reaction at constant temp and pressure equation
deltaG = deltaH - TdeltaS
knowing genetic code and the start codon and exon boundaries are known, it is possible to deduce the blank
primary structure
